Red azo dye.



UNITED STATES PATENT OFFICE.

ELBERFELD, GERMANY, ASSIGi-NORS TO FARBENFABRIKEN VORM. FRIEDR. BAYER & 00., OF ELBERFELD, GERMANY, A CORPORATION OF GERMANY,

RED AZO DYE.

No Drawing.

' Patented May 21, 1912. Serial No. 651,336.

To all whom it mayconcern:

Be it known that we, ANION OSSENBEGK and An'rI-iUR ZART, doctors of philosophy, chemists, citizens of the German Empire, residing, respectively, at Elberfeld .and Vohwi'nkel, near Elberfeld, Germany, have invented new and useful Improvements in Red Azo Dye, of which the following is a specification.

#Olir invention relates to the manufacture and production of a new azo dyestufi which is obtained by combining the diazotized 'monoa'zo, dyestufl' preparedfroni diazotized 3-chloro-2-toluidin-5-sulfonic' acid and anilin with '2-benzoylamino-5-naphthol-7-su1 tonic-acid. It is a red powder soluble in watrwith 'a'red coloration; yielding upon reduction with stannous chlorid and hydrochloric acid 5-chloro-2-toluidin 5-sulfonic acid, para-phenylenediamin and 2-benzoylamino 6 amino-5-naphthol-7-sulfonic acid;

v In order to illustrate the new process more fully the following example is given, the

parts being by we1glit:325.5 parts of the monoazo dyestufl:

' obtained from 3-chloro-2-toluidin-5-sulfonic according to the process of British Letters Patent No. 11343/99, are diazotized with 69 parts of sodium nitrite and hydrochloric acldand the diazo derivative is combined in acetic acid solution with 343 parts of benz0yl-2-amino 5 naphthol 7- sulfonic acid. As soon as the combination is complete the solution is heatedto about 70 C. and the dyestufl is salted out.

We claim The herein described new azo dyestufi of the formula:

which is a red powder soluble in water with a red coloration; yielding upon reduction with stannous chlorid and hydrochloric acid 5 chloro 2 toluidin 3 sulfonic acid,

- para-phenylenediamin and 2-benzoylamino- 6-amino- 5 naphthol 7 sulfonic acid; and dyeing cotton red fast to light, substantially as described.

In testimony whereof We have hereunto set our hands in the presence of two sub scribing witnesses.

A. Norma;

Copies 01' this patent may be obtained for five cents each, by addressing the Commissioner of Patents.

' Washington, D. 03 

